Childhood obesity is a major issue and puts children at risk of physical and psychological health complications. Some studies have evaluated obesity in autism in different countries. However there is few data on the rate of obesity in high-function autism (HFA).

To evaluate the weight status of children with HFA in Iran

This cross-sectional survey was carried out in autism specific schools of Tehran in 2010. In total 113 children with HFA ages 6–15 were evaluated. They were classified according to WHO references (2007) for body mass index (BMI) for age and sex as obese, overweight, healthy weight and underweight. We then examined the associations of weight status of these children with some variables and comorbodities.

The prevalence of obesity in children with HFA was 27.0%, overweight 13.0% and underweight 7.0%. There was a significant correlation between age and BMI (r = 0.26, Pvalue < 0.01). Underweight was associated with neurologic comorbidities (p < 0.05). The rate of obesity has not correlated with some other medical and psychiatric comorbidities, as well as sex, and parents’ weight status.

Prevalence of obesity in autistic children with high intelligence profile is high and at the same levels of both normal children and children with autistic spectrum disorders.